This application relates generally to a disc drive data storage device including an actuator assembly and more particularly to a method and apparatus for coupling one or more flex suspension assemblies to one or more actuator arms of an actuator assembly.
In a typical disc drive, one or more flex suspension assemblies (FSAs) each carry a head for reading and writing from and to one or more magnetic discs. An actuator assembly comprises one or more actuator arms used to carry the one or more FSAs and attached heads for placement over the magnetic discs for reading and writing to and from the magnetic discs. It is necessary to couple the one or more FSAs to the one or more actuator arms on the actuator assembly. This attachment process needs to be conducted for actuator assemblies provided in test apparatuses, which are utilized to test the mechanical and electrical properties of the FSAs, for multi-disc writers, which are used to write servo tracks and other data to multiple discs at one time, and to typical disc drives, which are used to store and retrieve data from a magnetic disc.
Historically, an FSA was coupled to an actuator arm using a mounting plate attached to an FSA, the mounting plate including a boss that was sized to fit into an opening defined in an actuator arm provided as part of an actuator assembly. With the boss in place, a swaging technique would be used to attach the boss to the actuator arm. The swaging technique involved passing one or more specifically sized balls through the boss so as to deform the boss relative to the opening in the actuator arm, thereby fixing the FSA in place.
However, current techniques used to fix the FSA to the actuator arm may alter the fly characteristics of the actuator arm. Stresses placed on an actuator arm during coupling and/or removal of the FSA may result in deformation of the actuator arm. An irregularly-shaped actuator arm can exhibit sporadic fly characteristics, causing vibrations, pitches, and rolls that may effect head placement over the magnetic disc. Further, current techniques impart stresses on the actuator arms such that a single actuator arm may only be used with several FSAs before the actuator arm must be replaced. In addition, prior art techniques may make it difficult or impossible to remove an FSA from an actuator arm, or, alternatively, prior art techniques for attaching the FSA to the actuator arm may not provide the necessary clamping force to maintain the coupling between the FSA and the actuator arm. Moreover, prior art materials used to make the actuator arms may exhibit magnetic properties that may interfere with reading and writing from and to the magnetic disc.
Accordingly there is a need for an improved system and method used to couple FSAs to actuator arms.
Against this backdrop the present invention has been developed. In an exemplary embodiment of the invention, an actuator assembly includes one or more actuator arms, wherein each of the actuator arms defines a clasp hole and a clamp-opening hole. In addition, a slot in the actuator arm runs between the clasp hole and the clamp-opening hole, and optionally, a second slot is defined in the actuator arm running from the clasp hole to a distal end of the actuator arm, thereby creating two clasp fingers.
A flex suspension assembly (FSA) is included with a protrusion, such as a boss, disposed on a proximal end and a head on a distal end of the FSA. In order to releasably couple the FSA to the actuator arm, a camming rod or other device is inserted into the clamp-opening hole. The camming rod is actuated to resiliently increase the diameter of the clasp hole so as to allow the boss disposed on the FSA to be inserted into the clasp hole. Further, once the boss is inserted and the camming rod removed from the clamp-opening hole, the clasp hole resiliently attempts to revert to its original diameter, thereby clamping and retaining the boss in the clasp hole. In this manner, the FSA is fixedly coupled to the actuator arm. The FSA can also be removed from the actuator arm in a similar manner.
These and various other features as well as advantages which characterize embodiments of the present invention will be apparent from a reading of the following detailed description and a review of the associated drawings.